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+CURRENT PRIORITIES
+=================================================
+Eliminate all crashes (DONEish)
+        Editing/deleting physical linkset (DONE)
+        Border crossing of physical linkset (DONE)
+Enable vehicle border crossings (at least as poorly as ODE)
+        Avatar created in previous region and not new region when crossing border
+        Vehicle recreated in new sim at small Z value (offset from root value?) (DONE)
+Calibrate turning radius
+limitMotorUp calibration (more down?)
+study PID motors (include 'efficiency' implementation
+        Add to avatar movement
+
+CRASHES
+=================================================
+20121129.1411: editting/moving phys object across region boundries causes crash
+    getPos-> btRigidBody::upcast -> getBodyType -> BOOM
+20121128.1600: mesh object not rezzing (no physics mesh).
+    Causes many errors. Doesn't stop after first error with box shape.
+    Eventually crashes when deleting the object.
+20121206.1434: rez Sam-pan into OSGrid BulletSim11 region
+        Immediate simulator crash. Mono does not output any stacktrace and
+        log just stops after reporting taint-time linking of the linkset.
+
+VEHICLES TODO LIST:
+=================================================
+Border crossing with linked vehicle causes crash
+Neb vehicle taking > 25ms of physics time!!
+Vehicles (Move smoothly)
+Add vehicle collisions so IsColliding is properly reported.
+        Needed for banking, limitMotorUp, movementLimiting, ...
+Some vehicles should not be able to turn if no speed or off ground.
+Cannot edit/move a vehicle being ridden: it jumps back to the origional position.
+Neb car jiggling left and right
+        Happens on terrain and any other mesh object. Flat cubes are much smoother.
+        This has been reduced but not eliminated.
+Light cycle falling over when driving
+Implement referenceFrame for all the motion routines.
+Angular motion around Z moves the vehicle in world Z and not vehicle Z in ODE.
+        Verify that angular motion specified around Z moves in the vehicle coordinates.
+Verify llGetVel() is returning a smooth and good value for vehicle movement.
+llGetVel() should return the root's velocity if requested in a child prim.
+Implement function efficiency for lineaar and angular motion.
+Should vehicle angular/linear movement friction happen after all the components
+        or does it only apply to the basic movement?
+After getting off a vehicle, the root prim is phantom (can be walked through)
+    Need to force a position update for the root prim after compound shape destruction
+Linkset explosion after three "rides" on Nebadon lite vehicle (LinksetConstraint)
+For limitMotorUp, use raycast down to find if vehicle is in the air.
+Remove vehicle angular velocity zeroing in BSPrim.UpdateProperties().
+        A kludge that isn't fixing the real problem of Bullet adding extra motion.
+
+BULLETSIM TODO LIST:
+=================================================
+Revisit CollisionMargin. Builders notice the 0.04 spacing between prims.
+Avatar height off after unsitting (floats off ground)
+        Editting appearance then moving restores.
+        Must not be initializing height when recreating capsule after unsit.
+Duplicating a physical prim causes old prim to jump away
+        Dup a phys prim and the original become unselected and thus interacts w/ selected prim.
+Scenes with hundred of thousands of static objects take a lot of physics CPU time.
+BSPrim.Force should set a continious force on the prim. The force should be
+        applied each tick.  Some limits?
+Gun sending shooter flying.
+Collision margin (gap between physical objects lying on each other)
+Boundry checking (crashes related to crossing boundry)
+    Add check for border edge position for avatars and objects.
+    Verify the events are created for border crossings.
+Avatar rotation (check out changes to ScenePresence for physical rotation)
+Avatar running (what does phys engine need to do?)
+Small physical objects do not interact correctly
+    Create chain of .5x.5x.1 torui and make all but top physical so to hang.
+        The chain will fall apart and pairs will dance around on ground
+    Chains of 1x1x.2 will stay connected but will dance.
+    Chains above 2x2x.4 are move stable and get stablier as torui get larger.
+Add PID motor for avatar movement (slow to stop, ...)
+setForce should set a constant force. Different than AddImpulse.
+Implement raycast.
+Implement ShapeCollection.Dispose()
+Implement water as a plain so raycasting and collisions can happen with same.
+Add osGetPhysicsEngineName() so scripters can tell whether BulletSim or ODE
+        Also osGetPhysicsEngineVerion() maybe.
+Linkset.Position and Linkset.Orientation requre rewrite to properly return
+        child position. LinksetConstraint acts like it's at taint time!!
+
+LINKSETS
+======================================================
+Linksets should allow collisions to individual children
+        Add LocalID to children shapes in LinksetCompound and create events for individuals
+LinksetCompound: when one of the children changes orientation (like tires
+        turning on a vehicle, the whole compound object is rebuilt. Optimize this
+        so orientation/position of individual children can change without a rebuild.
+Verify/think through scripts in children of linksets. What do they reference
+        and return when getting position, velocity, ...
+Confirm constraint linksets still work after making all the changes for compound linksets.
+Add 'changed' flag or similar to reduce the number of times a linkset is rebuilt.
+        For compound linksets, add ability to remove or reposition individual child shapes.
+Disable activity of passive linkset children.
+        Since the linkset is a compound object, the old prims are left lying
+        around and need to be phantomized so they don't collide, ...
+Speed up creation of large physical linksets
+        For instance, sitting in Neb's car (130 prims) takes several seconds to become physical
+Eliminate collisions between objects in a linkset. (LinksetConstraint)
+    Have UserPointer point to struct with localID and linksetID?
+    Objects in original linkset still collide with each other?
+
+MORE
+======================================================
+Find/remove avatar collision with ID=0.
+Test avatar walking up stairs. How does compare with SL.
+    Radius of the capsule affects ability to climb edges.
+Tune terrain/object friction to be closer to SL.
+Debounce avatar contact so legs don't keep folding up when standing.
+Implement LSL physics controls. Like STATUS_ROTATE_X.
+Add border extensions to terrain to help region crossings and objects leaving region.
+
+Performance test with lots of avatars. Can BulletSim support a thousand?
+Optimize collisions in C++: only send up to the object subscribed to collisions.
+    Use collision subscription and remove the collsion(A,B) and collision(B,A)
+Check whether SimMotionState needs large if statement (see TODO).
+
+Implement 'top colliders' info.
+Avatar jump
+Performance measurement and changes to make quicker.
+Implement detailed physics stats (GetStats()).
+
+Measure performance improvement from hulls
+Test not using ghost objects for volume detect implementation.
+Performance of closures and delegates for taint processing
+        Are there faster ways?
+        Is any slowdown introduced by the existing implementation significant?
+Is there are more efficient method of implementing pre and post step actions?
+        See http://www.codeproject.com/Articles/29922/Weak-Events-in-C
+
+Physics Arena central pyramid: why is one side permiable?
+
+INTERNAL IMPROVEMENT/CLEANUP
+=================================================
+Consider moving prim/character body and shape destruction in destroy()
+        to postTimeTime rather than protecting all the potential sets that
+        might have been queued up.
+Remove unused fields from ShapeData (not used in API2)
+Breakout code for mesh/hull/compound/native into separate BSShape* classes
+    Standardize access to building and reference code.
+        The skeleton classes are in the sources but are not complete or linked in.
+Make BSBody and BSShape real classes to centralize creation/changin/destruction
+        Convert state and parameter calls from BulletSimAPI direct calls to
+                calls on BSBody and BSShape
+Generalize Dynamics and PID with standardized motors.
+Generalize Linkset and vehicles into PropertyManagers
+    Methods for Refresh, RemoveBodyDependencies, RestoreBodyDependencies
+        Potentially add events for shape destruction, etc.
+Complete implemention of preStepActions
+        Replace vehicle step call with prestep event.
+        Is there a need for postStepActions? postStepTaints?
+Implement linkset by setting position of children when root updated. (LinksetManual)
+        Linkset implementation using manual prim movement.
+LinkablePrim class? Would that simplify/centralize the linkset logic?
+BSScene.UpdateParameterSet() is broken. How to set params on objects?
+Remove HeightmapInfo from terrain specification
+    Since C++ code does not need terrain height, this structure et al are not needed.
+Add floating motor for BS_FLOATS_ON_WATER so prim and avatar will
+    bob at the water level. BSPrim.PositionSanityCheck().
+Should taints check for existance or activeness of target?
+        When destroying linksets/etc, taints can be generated for objects that are
+        actually gone when the taint happens. Crashes don't happen because the taint closure
+        keeps the object from being freed, but that is just an accident.
+        Possibly have and 'active' flag that is checked by the taint processor?
+
+THREADING
+=================================================
+Do taint action immediately if not actually executing Bullet.
+        Add lock around Bullet execution and just do taint actions if simulation is not happening.
+
+DONE DONE DONE DONE
+=================================================
+Cleanup code in BSDynamics by using motors. (Resolution: started)
+Consider implementing terrain with a mesh rather than heightmap. (Resolution: done)
+    Would have better and adjustable resolution.
+Build terrain mesh so heighmap is height of the center of the square meter.
+    Resolution: NOT DONE: SL and ODE define meter square as being at one corner with one diagional.
+Terrain as mesh. (Resolution: done)
+How are static linksets seen by the physics engine?
+    Resolution: they are not linked in physics. When moved, all the children are repositioned.
+Convert BSCharacter to use all API2 (Resolution: done)
+Avatar pushing difficult (too heavy?)
+Use asset service passed to BulletSim to get sculptie bodies, etc. (Resolution: done)
+Remove old code in DLL (all non-API2 stuff). (Resolution: done)
+Measurements of mega-physical prim performance (with graph) (Resolution: done, email)
+Debug Bullet internal stats output (why is timing all wrong?)
+        Resolution: Bullet stats logging only works with a single instance of Bullet (one region).
+Implement meshes or just verify that they work. (Resolution: they do!)
+Do prim hash codes work for sculpties and meshes? (Resolution: yes)
+Linkset implementation using compound shapes. (Resolution: implemented LinksetCompound)
+    Compound shapes will need the LocalID in the shapes and collision
+    processing to get it from there.
+Light cycle not banking (Resolution: It doesn't. Banking is roll adding yaw.)
+Package Bullet source mods for Bullet internal stats output
+        (Resolution: move code into WorldData.h rather than relying on patches)
+Single prim vehicles don't seem to properly vehiclize.
+        (Resolution: mass was not getting set properly for single prim linksets)
+Add material type linkage and input all the material property definitions.
+        Skeleton classes and table are in the sources but are not filled or used.
+        (Resolution: